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All this talk of gooseneck trailers reminds me of a problem I am facing. I will be hauling my '46 to the ATHS Convention in AL in May behind the '72 GMC. The rear springs are very stiff and am afraid that the harsh ride could be be rough on the gooseneck on my trailer. I was reading on another forum where guys are removing leaves from the sring pack to get a better ride. One guy went from 12 to 3 leaves on his B model Mack and is very happy with the ride. Does any one here have any experience with something like this? How many to remove and which ones? One guy cut the ends off leaving only a short piece to act as a spacer and other people have install blocks to replace the missing spring thickness. I don't want to do anything that would make the remaining leaves unsave and this truck will never haul anything heavier than my little gn. Not cutting the springs sounds like a better way to go so if I ever sold the truck the new owner would be able to put them back.
Bill

Have you driven the truck with the loaded gooseneck behind it?

My first concern would be the load that trailer represents.

My second would be the anti-sway aspect of those springs. You don't want your truck rolling side to side and your stiff leaf springs are one of the primary ways the truck stays level.

Does the guy with the Mack haul a load with it?

Yes , I think he hauls a gn trailer with it that has a 3000lb pin weight. I don't know what the weight my trailer is on the ball but I doubt it would be much more than that. Its a 14,000 gvw trailer and the truck and golf cart that I haul on it only weight abot 6,800.
I have not hauled with the truck yet. I just feel like the low weight of the trailer and the rock like ride of the truck could be a problem.

Do you have a spring shop near by?
Call or take the truck over there, and explain what you want to achieve.
They should have some professional advice and recommendations on what to do. They can even do the work, and they will have or can make new U-bolts, as you should never reuse suspension U-bolts.

Grigg

Perhaps an airride system off another truck would work. Generally they are less harsh then spring ride. More expensive than staying with springs.Some folks just cut the frame and weld used cutoff suspension in place would also be a way to stretch the frame if you wanted to add a sleeper. Longer wheelbase would most likely improve ride as well. Newer cuttoff suspension and axles may also give you the option of a higher gear ratio since you won't be hauling heavy loads. Higher mph possible fuel savings. example 69 frieghtliner 671, 10 speed 4:11 rears,71 freightliner 8V71 13 speed 4:33 rears, 73 GMC 8V71 13speed 4:11 rears compare to the truck I'm running now with 3:25 rears but it develops twice the torque as the old DD. rpm 1550 at 75 vs 71 at 2100 with the older trucks.

I have a spring shop in mind, I guess I would love to be able to attempt something like this myself. I'm mostly curious which leaves would be removed with out any adverse effects. I considered the airbag route but don't have the funds for that kind of modification right now. I have read that an unloaded air ride can still be a little harsh so, money wise, and for all around use of the truck, the leaf removal may be the way to go. Although..... I would love to be able to run down the road at 60 or 65 without being so wound out. At 60 mph, the tack is at about 1900. 65 its around 2000-2100 and you know it. What ratio would you reccomend for this truck with the way I intend on using it?

What is your tire outside diameter?
Transmission ratio in high gear?
Current rear axle ratio?

Plug it all in here http://www.onlineconversion.com/bigger_tires.htm last one on the page.

You'll probably want 1,600 rpm at cruising speed, be it 65 mph or 70, or whatever you like. That should be OK for the 6-71 and the intended load, and result in reasonable mileage and reduced "noise" if you call it that

You'll want to turn no more than 2,300 rpm at your fastest speed So if you might need to go 80 mph every now and then for a short bit plan on that too.

Might be you need a single speed rear axle to get fast enough ratio choices.

Would also be nice to have a Roadranger 10 or 13 speed overdrive. If so then I'm guessing 3.54 axle gears with the 0.80 OD in the Roadranger.

How fast do you want to travel, and what are your current measurements and ratios?

Grigg